Organelle with its own DNA, division, and partial autonomy Which cellular organelle typically contains its own DNA, divides within the cell, and exhibits a degree of genetic and metabolic autonomy?

Introduction / Context:
Some eukaryotic organelles retain features reminiscent of ancient endosymbiotic origins, including their own genomes and semi-independent division. Recognizing which organelles possess DNA and replicate autonomously is central to understanding the endosymbiotic theory and organelle biogenesis in plants and algae.

Given Data / Assumptions:

• The question targets organelles that contain DNA and divide.
• Endosymbiotic organelles include mitochondria and chloroplasts; both possess circular DNA and bacterial-like ribosomes.
• Other compartments (Golgi, lysosomes, peroxisomes) do not carry their own DNA.

Concept / Approach:

Chloroplasts (in plants and algae) harbor their own genome, transcribe and translate a subset of proteins, and replicate by binary fission-like mechanisms. Although most chloroplast proteins are encoded in the nuclear genome and imported, the organelle maintains partial autonomy. Mitochondria are another correct example in general, but among the provided options, chloroplast is the single best answer.

Step-by-Step Solution:

Verification / Alternative check:

Texts on plant cell biology note plastid DNA, plastid division rings, and gene expression machinery similar to cyanobacteria, supporting an ancient symbiosis origin.

Why Other Options Are Wrong:

• Golgi apparatus: Involved in protein modification and trafficking; lacks DNA.
• Ribosome: A complex of RNA and proteins, not a membrane-bound organelle with its own genome.
• Peroxisomes: Self-replicate but do not contain DNA; their proteins are nuclear-encoded and imported.
• Lysosome: Digestive organelle with hydrolytic enzymes; no DNA present.

Common Pitfalls:

• Confusing peroxisome self-duplication with genetic autonomy; peroxisomes bud and grow but are entirely nuclear-programmed.
• Assuming any compartment that divides must have DNA; that is not necessarily true.

Final Answer:

Chloroplast